1. Field of the Invention
This invention relates to novel compounds which inhibit or modulate the activity of protein kinases and to pharmaceutical compositions comprising such compounds. This invention also relates to methods of treating diseases or medical conditions mediated by protein kinases using such compounds.
2. State of the Art
Protein kinases are enzymes which catalyze the phosphorylation of hydroxy groups on tyrosine, serine and threonine residues of proteins. See, for example, Hardie, G. and Hanks, S. (1995) The Protein Kinase Facts Book, I and II, Academic Press, San Diego, Calif.; Stover, D. R. et al., Current Opin in Drug Discovery, (1999) 2(4), 274–285; Adams, J. L., Current Opin. in Drug Discovery, (1999) 2(2), 96–109; and Lawrence D. S. et al., Pharmacol. Ther. (1998) 77(2), 81–114. By doing so, protein kinases mediate virtually all aspects of cell life including cell growth, cell differentiation and cell proliferation. In this regard, abnormal activity of protein kinases has been associated with a host of diseases or medical disorders, ranging from relatively non-life threatening diseases such as psoriasis to extremely virulent diseases such as glioblastoma (brain cancer). See, for example, Levitzki, A. et al., Science, (1995) 267, 1782–1788.
Accordingly, a need exists for compounds and compositions which inhibit or modulate the activity of protein kinases.